Berberine ameliorates hyperglycemia in alloxan-induced diabetic C57BL/6 mice through activation of Akt signaling pathway

• Published in: ENDOCRINE JOURNAL 2011, Vol.58(9), pp.761-768
• Main Authors: Xie, Xi, Li, Wenyuan, Lan, Tian, Liu, Weihua, Peng, Jing, Huang, Kaipeng, Huang, Juan, Shen, Xiaoyan, Liu, Peiqing, Huang, Heqing
• Format: Article
• Language: English
• Subjects: Akt signaling pathway; Animals; Berberine; Berberine - pharmacology; Blood Glucose - analysis; Blotting, Western; Diabetes Mellitus, Experimental - drug therapy; Diabetes Mellitus, Experimental - enzymology; Diabetes Mellitus, Experimental - metabolism; Diabetic mouse; Glucokinase; Glucokinase - genetics; Glucokinase - metabolism; Glycogen - analysis; Glycogen - metabolism; Glycogen Synthase Kinase 3 - genetics; Glycogen Synthase Kinase 3 - metabolism; Glycogen Synthase Kinase 3 beta; GSK-3β; Hyperglycemia - drug therapy; Hyperglycemia - enzymology; Hyperglycemia - metabolism; Male; Mice; Mice, Inbred C57BL; Phosphorylation; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - metabolism; Random Allocation; Reverse Transcriptase Polymerase Chain Reaction; RNA - chemistry; RNA - genetics; Signal Transduction - drug effects; Specific Pathogen-Free Organisms
• ISSN: 0918-8959; 1348-4540
• DOI: 10.1507/endocrj.K11E-024

Recently, it is implicated that the abnormality of Akt signaling pathway is involved in the diabetic pathology. Previous studies have demonstrated that berberine could decrease blood glucose by elevating liver glycogen synthesis. However, the underlying mechanism is still unclear. In the present study, we investigated the effects of berberine on fasting blood glucose, liver glycogen, Akt, Glycogen synthase kinase-3, glucokinase and insulin receptor substrate (IRS) in alloxan-induced diabetic mice, exploring its possible hypoglycemic mechanism. We found that in alloxan-induced diabetic mice, the high blood glucose was significantly lowered by berberine treatment. Liver glycogen content, the expression and activity of glucokinase and the phosphorylated Akt and IRS were all significantly reduced in diabetic mice whereas berberine blocked these changes. Berberine also depressed the increasing of phosphorylated GSK-3β in diabetic mice. Collectively, Berberine upregulates the activity of Akt possibly via insulin signaling pathway, eventually lowering high blood glucose in alloxan-induced diabetic mice.